| 64 |
|
which may be a sequence of Radiance pictures as understood by |
| 65 |
|
.I ra_rgbe(1) |
| 66 |
|
in the case of a multi-column input matrix. |
| 67 |
< |
(Note that there is currently no Radiance tool that understands a |
| 68 |
< |
concatenated series of float or spectral pictures.)\0 |
| 67 |
> |
(Note that there is currently no Radiance tool that fully |
| 68 |
> |
handles a concatenated series of float or spectral pictures.)\0 |
| 69 |
|
.PP |
| 70 |
|
The |
| 71 |
|
.I \-N |
| 85 |
|
Window2.dmx - | pvsum view%03d.hdr > view_6-21-12.hdr |
| 86 |
|
.PP |
| 87 |
|
To compute a set of hourly spectral pictures at SFO airport |
| 88 |
< |
from a weather tape and set of Tregenza component pictures: |
| 88 |
> |
from a weather tape and set of Tregenza component pictures using |
| 89 |
> |
10 processes: |
| 90 |
|
.IP "" .2i |
| 91 |
< |
gensdaymtx sfo.epw | pvsum -o timestep%04d.hsr tregcomp%03d.hsr |
| 91 |
> |
gensdaymtx -of sfo.epw | pvsum -o timestep%04d.hsr -N 10 tregcomp%03d.hsr |
| 92 |
|
.SH NOTES |
| 93 |
< |
This tool is annoyingly similar to |
| 93 |
> |
This tool overlaps with |
| 94 |
|
.I dctimestep, |
| 95 |
< |
but provides some important capabilities. |
| 96 |
< |
First, |
| 95 |
> |
but provides some missing capabilities. |
| 96 |
> |
Foremost, |
| 97 |
|
.I pvsum |
| 98 |
|
reads and can produce spectral pictures and matrices, whereas |
| 99 |
|
.I dctimestep |
| 100 |
|
expects and requires 3-component pictures and matrices throughout. |
| 101 |
< |
Changing the data structures in |
| 101 |
< |
.I dctimestep |
| 102 |
< |
proved too difficult and likely to |
| 103 |
< |
lead to a less efficient implementation, especially on systems with |
| 104 |
< |
limited memory. |
| 105 |
< |
In contrast, |
| 101 |
> |
In addition, |
| 102 |
|
.I pvsum |
| 103 |
|
accelerates picture sums on Unix systems with more |
| 104 |
< |
memory and processint ability. |
| 105 |
< |
Second, operation was simplified by focusing on the Daylight Coefficient |
| 104 |
> |
memory and CPU cores. |
| 105 |
> |
Operations were simplified by focusing on the Daylight Coefficient |
| 106 |
|
command form, where the DC matrix is represented as a collection of |
| 107 |
|
pictures. |
| 108 |
< |
By excluding the three or four other operation modes of |
| 113 |
< |
.I dctimestep, |
| 114 |
< |
new features could be explored in |
| 115 |
< |
.I pvsum. |
| 116 |
< |
For example, |
| 108 |
> |
Finally, |
| 109 |
|
.I pvsum |
| 110 |
< |
can write picture data to a series of commands, which |
| 111 |
< |
.I dctimestep |
| 120 |
< |
does not support. |
| 110 |
> |
offers more flexible floating-point support and |
| 111 |
> |
can output to commands as well as files. |
| 112 |
|
.SH AUTHOR |
| 113 |
|
Greg Ward |
| 114 |
|
.SH "SEE ALSO" |
